The present invention is directed to a device for sensing an amount of force applied to it, conversion of that force to an output of a different type of energy, and transmission of that output from the device for further processing and evaluation to indicate the amount of said force present at any given particular time. More particularly, the invention is directed to an energy conversion and transmission device employing pressure sensitive elements and producing a continuous, or analog, output in response to forces to which it is subjected.
While such energy conversion and transmission devices for production of analog outputs are not unknown in the prior art, most such devices have, at least in part, incorporated therein some mechanical linkage between the force sensing element and the output producing elements. These mechanical linkages vary in complexity, but generally involve a plurality of levers, cams, or the like to transmit the mechanical deflection imposed upon the device by the force to be detected to the output producing element of the device. Output producing elements may, for example, be potentiometers, variable inductance coils, variable capacitors having movable plates, and the like. It is a general maxim that the more moving parts contained in a device, the more there is that can go wrong with that device. Conversely, the fewer the parts contained in a device, the less prone the device is to breakdown and, hence, the more reliable the device. Thus, the most reliable device is often the device having the fewest moving parts therein.
The economics of a device are also of significant importance and such characteristics as a lower cost of construction, simplicity of construction, durability and a wide range of applications for a given technology are all important considerations in determining the economic success of a device.